Means for the hydraulic transmission of power



Nov. 6, 1934. w PATERSON 1,979,570

MEANS FOR THE HYDRAULIC TRANSMISSION OF POWER Filed Dec. 15. 1930 2 Sheets-Sheet l Fqi. 21

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MEANS FOR THE HYDRAULIC TRANSMISSION OF POWER Filed Dec. 15. 1930 2 Sheets-Sheet 2 y & $993.

Patented Nov. 6, 1934 STATES :P we FFi CE -MEANS FOR THEHYDRAULIC TRANSMIS- SIQN OF .POWER Thomas Watson Paterson, Allerton, Liverpool, England Application December 15, 1930, Serial No. 502,333 [In GreatBritaimFebruary 6, 1930 4 'Claims. (Cl. 192-60) provide improvements in-hydraulictorque transmittingapparatus of the kind: employing pistons orplungersghereinaftei' referred to as pistons, accommodated in -radially disposed 1 cylinders in a rotor arrangedto function within aconfining casing 'provided'with a suitable .guide'track, .or 'the like, :to impart .reciprocal motion to the pistons.

coupled directto thepowerproducing unit, and the casingcontaining the rotor coupled tothe ipower receiving unit, the transmission of such :power from the drivingto the-drivenelement "being dependent upon thehydraulic transmitter interposedibetween these two elements.

According to thepresent invention, the rotor,

for the purposeof convenience herein coupled'to the power producing unit, .is provided with a plurality ofradially arranged cylinders in which the pistons are reciprocallydisposed, whilst the pistons have their peripheral orterminal ends in contact with a toothed or plain-surfaced guide track on'the confining casing throughthe medium of toothed wheels or rollersto ensure free movement of the pistons about the guide'track. The guide track itself is preferably arranged as a true ring within the confining casing, but axially offset relative to the axis of thecasing,

140 so providing an eccentrictrackabout-which the toothed wheels or rollers at thepiston'ends may rotate to'impart reciprocal motion'to the: pistons when the rotor is set 'in motion. The pistons are arranged so that "each diametrically opposed pair are positively connected; thusreciprocal movement of any one piston withinits working cylinder will sympathetically effect corresponding reciprocalzmovement of its opposed piston, such movement of the pistons beingheifected.

.50 solely through their operative engagement with the guide track, i. e. irrespective of the-agency 'of liquid :medium.

Further, in order that the pistons in Y their drivingeffort against theconfiningcasing may not be =ren'dered inoperative by' back thrust, the

The rotor bearing the pistonsmayrbe wheels or rollers which operate on the guide track of the confining casing are revolubly supported in members movably mounted on the outer ends of the pistons and .pivotally con nected with the rotor. Consequently, back thrust is absorbed :by the pivotal connecting links and their anchoring pins and the pistons may reciprocate freely and truly'within their cylinders-withoutbeing subject to such thrust.

Normally, the cylinders of the rotor are.filled to their maximum capacity with oil or other suitable liquid-medium, hereinafter referred to as .oil, so that adesirable working volume of such oil is maintained between therespective pistons and their confining cylinders, and the cylinders are. provided with regulable intercommunicating ports so that transference of the oil from cylinder to cylinder may be freely effected, or such transference restricted within required limits,

orif-desired, completely obstructed. The con- ,fining casing is also normally filled to its maximum capacity with oil to the exclusion of atmospheric air.

.If desired, supplemental oil .chambers with automatic replenishing means may be used for replacing any oil lost by leakage from-the confining chamber after prolonged usage.

I will further describemy invention-with the aid of the accompanying sheet of explanatory drawings which illustrate, by way of examples only, several modes of carrying the same into effect.

In said drawings:-

Figs. 1 and 2 are sections-taken at right angles to each otherof one form ofapparatus constructed in accordance with the invention.

Fig. 3 is a face View of a valve for manually controlling the apparatus. 1 i

:Fig. 4 is a view illustrating a modification.

Inthe several views like characters of refer- :encedenote like or equivalent parts wherever they occur.

Referring first to Figs. 1, 2 and 3, 1 indicates a driving shaft and 2 a driven shaft. Disposed inradially-arranged cylinders 3 in a rotor disc .4 secured to shaft 1 are :pist-ons 5 provided at their .outer or terminal ends with toothed. wheels 6 which mesh with an internally toothed.

guide track Tarranged eccentrically to the axis of therespective shafts 1, .2. Said guidetrack '7 may be in the form of a one or twoepiece ring fixed to the inner wall of a two-piece casing or chamber 8 provided at an end of shaft 2.

"Normally, rotor disc 4 is filled with oil so as to ensurea suificientworking volume between pistons 5, whilst casing 8 is also filled with oil in order to prevent leakage of the oil from the working cylinders 3 of the rotor into its confining casing.

Said pistons 5 are rigidly connected in diametrically opposed pairs by means of connecting rods 9 so that each pair will operate as a single unit. Thus any one piston will, in traversing guide track '7, reciprocate within its cylinder 3 and positively effect corresponding reciprocation of its opposed or connecting piston, such.

movement of the pistons 5 being effected inde-- through the medium of a pivotal fork or drag link 14, said fork acting through an axially slidable collar 15, a fixed pin or projection 16 on the collar, and an inclined slot or groove 17 in the valve spindle 18 to partially rotate the latter and so the plate valve 12 which places the cylinders 3 in communication with each other, or isolates these cylinders from each other, as the case may be.

When said peripheral recesses 13 of plate valve 12 are in register or coincidence with the cylinder ports 10, as illustrated in Figs. 1 and 2, the oil contained in the several cylinders 3 is permitted to freely circulate from cylinder to cylinder so that rotor disc 4 and pistons 5 will revolve with shaft 1 without imparting rotary motion to casing 8, the opposed pairs of pistons being merely maintained in operative contact with the guide track '7 of said casing by their connecting rods 9, whilst the oil is continually injected into and ejected from the working cylinders 3 due to the fact that each piston recedes into and proceeds from its cylinder- -thereby making one complete reciprocal movement within its cylinder-in travelling once around guide track 7.

On the other hand, when the recesses 13 of plate valve 12 are moved out of register with the cylinder ports 10 the latter are sealed or closed by the rim portions 19 of the plate valve, and the oil then contained in each cylinder 3 is trapped: further movement of the respective pairs of pistons 5 is thus prevented and the toothed wheels 6 of those pistons projecting somewhat from their cylinders will, in the continued rotation of driving shaft 1 and rotor disc 4, become locked with guide track '7 of casing 8 and so rotate driven shaft 2 solid with shaft 1.

Now if restriction be imposed to the free passage of the oil from cylinder to cylinder by partial rotation of plate valve 12, retardation of j the pistons reciprocal function is produced, and.

as the pistons are proceeding rotationally in unit time, retardation of reciprocal movement must result in either one or other of two actions, namely, rotational movement of casing 8 is effected, or driving shaft 1 is retarded in its rota-- tional speed. This will apply throughout the workable range of the apparatus, from the state of free passage of oil between the several cylinders 3, proceeding by controllably small-differences of restriction, until there is finally reached a state where total obstruction to oil transference from cylinder to cylinder is established, and at this stage positive connection or direct drive between rotor disc 4 and casing 8 is reached, as previously described; the small differences of restriction to free flow of the oil are thereby responsively reflected in relative variations in speed between shafts 1 and 2 at the will of the operator, by actuation of plate valve 12. In. short, by a simple regulation of said plate valve, the available area of cylinder ports 10 may be minutely varied at will, and as each minute variation in the available area of the ports causes a slight difference of speed between rotor disc 4 and casing 8, any desired speed ratiosrang ing from free movement of the driving element relative to the driven element to positive or direct coupling of these elements-may be selected according to increase or decrease in the size of cylinder ports 10. t

It will, however, be realized that if the speed of rotation of the power-producing element coupled to the rotor disc 4 is capable of variation, as in the case of an internal combustion engine of a motor road vehicle, an infinitely variable speed ratio within any predetermined or selected range may be obtained with appropriately set cylinder ports 10, by reason of the fact that increase of engine speed is reflected in increase of re-active effort on the part of the oil contained in the rotor disc 4. Under certain con-" ditions, therefore, the manually operable plate valve 12'may'be omitted, although it is desirable to employ this valve as a means of slightly varying the setting of cylinder ports 10 to compensate for differences in working COlldltlOXl-SPIIU as it will be readily apparent that the viscosity of the ,oil in rotor disc 4 and so its speed of transference from cylinder to cylinder will be affected by diiferences in the load and also in the temperature of the apparatus.

It is to be noted that as diametrically opposed pistons 5 are attached by means of connecting rods 9 the possibility of independent movement of any one piston within its cylinder 3 relativeto its co-acting piston is definitely pre- Vented with the result that leakage of oil past thepist'on into casing 8 cannot take-place since displacement has not occurred. Under such conditions, the oil in the casing and in rotor disc 4 is in a state of equilibrium, providing, of-125 course, casing 8 is maintained filled with oil to its maximum capacity.

The toothed wheels 6 which operate on guide track 7 are carried by suitable bearing members 20 which are themselves slidably mounted 011*" the outer ends of the pistons 5 and pivotally connected by metal straps or links 21- to the .rotor disc 4. Thus it will be seen that backthrust imposed by casing 8 on the driving element will be absorbcd'by said pivotal'connect-C 35 ing straps or links: 21 and their anchoring pins 22, and the pistons 5 will, therefore, reciprocate freely and truly within their cylinders 3 without being subject to such thrust. Moreover, by

, of oil on the face of this valve and so leakage '15 of qlil from the central cavity 11 of rotor disc 4 into the valve spindle passage 25 is practically eliminated. Suitable spring rings, may, howev r, be provided on valve spindle 18 in order to reduce oil loss between the valve spindle and its passage 25.

In addition, there is formed in driving shaft Z a helical groove or recess 26 which acts as an impeller to return to casing 8 any oil which may find its way between this shaft and its bearing sleeve 2'? during differential rotation of rotor and casing, a suitable packing washer 28 and adjusting gland 29 being also fitted on an end of easing 8 toprevent leakage of oil through said sleeve 2'7 of the casing.

Further, there are formed on casing 8 appropriately spaced receptacles 30 containing supplementary supplies of oil for replacing any oil which may escape from said casing 8 after prolonged usage, the oil being automatically injected through ball-controlled apertures 31- when the apparatus is quiescentby means of spring-loaded plungers 32.

It is to be understood that various alterations or modifications as are deemed necessary may be made to the apparatus hereinbefore described without departing from the spirit and scope of the invention as defined by the claims, and in this connection it will be seen that Fig. 4 of the accompanying drawings shows a guide track having a plain inner surface i upon which the peripheries of plain rollers or discs may operate such rollers or discs being, of course, mounted on the terminal ends of the pistons 5 in substitution for the toothed wheels 6, as hereinbefore described.

In an alternative mode of construction, shaft 2 may function as a driving shaft and shaft 1 as a driven shaft. 7

It will also be understood that sympathetic reciprocal motion of the pistons may be effected operatively connecting the same in any other convenient manner other than that already described.

What I claim as my inventionand desire to secure by Letters Patent is:-

1. Hydraulic torque transmitting apparatus embodying driving and driven shafts and means for changing their relative speed comprising on one shaft a casing provided with a guide track, and on the other shaft a rotor confined Within said casing and provided with radially-disposed cylinders having intercommunicating ports and means to control the passage of liquid through said ports; and pistons accommodated in said rotor cylinders and directly connected in pairs by rigid connecting elements whereby reciprocation of any one piston will sympathetically effect corresponding reciprocal motion of 7 its opposed piston without the agency of liquid in the apparatus; and rollable elements mounted on the outer ends of said pistons and maintained in operative engagement with said guide track of the confining casing by said rigid connecting elements of the pistons, said rollable elements being revolubly supported in bearing members movably mounted on the outer ends of the pistons and pivotally connected with said rotor to permit true reciprocation of said pistons within their respective cylinders.

2. Hydraulic torque transmitting apparatus embodying driving and driven shafts and means for changing their relative speed comprising on one shaft a casing provided with a toothed guide track, and on the other shaft a rotor confined within said casing and provided with radially disposed cylinders having intercommunicating ports and means to control the passage of liquid through said ports; pistons accommodated in said rotor cylinders and directly connected in pairs by metal rods passing through apertures in the rotor into engagement with the inner ends of opposed pistons; bearing members slidably supported on guides provided on the outer ends of said pistons; toothed wheels revolubly mounted on said movable bearing members and maintained in meshing engagement with said toothed guide track of the confining casing by said direct connecting rods of the pistons; and. links pivotally connecting the toothed wheels of individual pistons to adjacent portions of the rotor.

3. Hydraulic torque transmitting apparatus embodying driving and driven shafts and means for changing their relative speed comprising on one shaft a casing provided with a guide track, and on the other shaft a rotor confined within said casing and provided with radially-disposed 5 cylinders having intercommunicating ports and means to control the passage of liquid through said ports; pistons accommodated in said rotor cylinders and directly connected in diametrically-opposed pairs by rigid connecting elements; bearing members movably mounted on the outer ends of said pistons; rollable elements pivotally connected with the rotor and revolubly mounted on said bearing members to operatively connect the pistons with said guide track of the confining casing; and means provided on said confining casing to automatically maintain a maximum working volume of liquid within said casing and. the rotor.

4. Hydraulic torque transmitting apparatus embodying driving and driven shafts and means for changing their relative speed comprising on one shaft a casing provided with a guide track, and on the other shaft a rotor confined within said casing and provided with radially-disposed 125 cylinders having intercommunicating ports and means to control the passage of liquid through said ports; pistons accommodated in said rotor cylinders and directly connected in diametrically opposed pairs by rigid connecting elements; 130 bearing members movably mounted on the outer ends of said pistons; rollable elements pivotally connected with the rotor and revolubly mounted on said bearing members to operatively connect the pistons with said guide track of the confin- 135 ing casing; and supplementary liquid receptacles fitted externally of the confining casing and provided with spring-loaded ejecting members to automatically inject such liquid by way of nonreturn means into the confining casing.

THOMAS WATSON PATERSON. 

